Lift cutting die and process



Feb. 9,1937. F. EXLEY v LIFT CUTTING DIE AND PROCESS Filed July 18, 19362 Sheets-Sheet 1 Feb. 9, 1937. 1.. F. EXLEY LIFT CUTTING DIE AND PROCESSFiled July 18, 1936 2 Sheets-Sheet 2 w ri Patented Feb. 9, 1937 PATENT()FFIQE LIFT CUTTING DIE AND PROCESS Leo F. Exley, Johnson City, N. Y.,assignor to Endicott Johnson Corporation, Endicott, N. Y., a corporationof New York Application July 18, 1936, Serial No. 91,385

5 Claims.

This invention includes a novel cutting die, and novel feeding mechanismfor use in connection with the die. The novel die is particularlydesigned for blanking or cutting out all sheet materials used in theconstruction of shoes or footwear, such as heel lifts, box toes,counters, heel reinforcing pieces, linings or any other part of a shoe,especially those blanks which have one straight, or substantiallystraight edge, and one object of my invention is to reduce waste ofmaterial and enable more blanks to be cut from a given size of sheetthan has heretofore been possible.

Another object is to provide improved means for feeding the sheet ofmaterial to and between the die and cutting block.

The blank cutting machine commonly used has a reciprocable plungercarrying a cutting block adjustable in relation to a blank cutting diemounted on a support below the cutting block, such support having anopening approximately of the same shape and usually larger than thecutting edge of the die. When such machine is in operation the plungeris reciprocated up and down, and the sheet of material, such as leatherboard, from which the blanks such as heel lifts or the like are to becut, is intermittently fed or pushed between the cutting die and blockby feed rolls; and blanks are successively cut out of the sheet adjacentthe inner edge of the material and pass down through the die and itssupport.

In such machine the feed rolls are located in advance of the die (inrelation to the direction of travel of the sheet being cut) and on theshafts of the feed rolls are discs which separate the portion of thesheet from which the blanks are to be cut from the body of the sheet, asand before the successive blanks are cut therefrom.

The discs in separating the strip from the main portion of the sheet,break and crush the adjacent edges of the strip and sheet, and sodisturb and displace the fibres therein as to form a considerableuseless spongy margin on both the strip to be cut and on the adjacentedge of the sheet, which edge must be presented to the back gauge in thenext subsequent cutting operation. Due to the production of such spongymargins, the shearing discs must be so located in relation to thecutting die that a sufficiently wide margin must be left uncut on eachside of the strip in order that no portion of the spoiled margins may beincluded in the cut blank. Such comparatively wide margins heretoforenecessarily left on both sides of the strip from which the blanks arecut result in a high percentage of waste material.

My invention overcomes and eliminates the waste and defects in thepresent blank cutting mechanism. One essential of my invention is thepeculiar construction of the cutting die and another the novelarrangement of the stock feeding mechanism. To enable others tounderstand and utilize my invention I will explain the same withreference to the accompanying drawings which illustrate a practicalembodiment of my invention, and in the claims the essentials of theinvention and novel features of construction and combination of partsfor which protection is desired are summarized.

In said drawings:

Fig. 1 shows parts of a lift cutting machine equipped with myimprovements. Fig. 2 is a plan of the cutting die. Fig. 3 is a top viewof the die. Fig. 4 is a sectional view of the die on the line 4-4, Fig.3. Fig. 5 is a diagrammatic figure illustrating the action of myinvention. Fig. 6 is a detail view of part of a lift strip cut by mymachine. Fig. '7 is a detail view of a lift strip cut by the heretoforeused machines. Fig. 8 is a view of a plural lift cutting die; and Fig. 9is a view of a part of the strip cut by die H.

The cutting die While I do not limit my invention to the cutting of heellifts, I have shown parts of a heel lift cutting machine and die in thedrawings as an illustration of one embodiment of the invention primarilybecause such heel lift blanks are usually cut from leatherboard and haveat least one straight, or nearly straight, edge.

The lift cutting die as shown in Figs. 2, 3 and. 4 has a body portion Iconforming in contour to the lift to be cut, and has a projection la atone straight or nearly straight side extending in line with suchstraightside. The extreme end lg of the projection la. is curved in slightly toinsure a positive and complete cut-off in event the position of theboard is slightly altered in its passage through the machine by carelesshandling. Said die is provided at its base with a perforated projectinglug le and flange If for engagement of bolts l h by which it is attachedto the base Ik. Fig. 1.

In setting-up the machine preparatory to operation, the die is set sothat the straight portion of the side of the die and the projection Iawill be exactly parallel to the direction of travel of the sheet, and asthe sheet progresses through the machine lifts are out and at the I sametime the projection Ia cuts off the small irregular shaped piece left bythe preceding lift cut-out. The cooperation of the projection la and theadjacent straight side of the die leaves the edge of the body of thesheet straight and true and in perfect condition to be placed di rectlyagainst the back gauge and repeat the operation just described.

The die is mounted upon the table of support 2 of the die cuttingmachine, in the usual manner (see Fig. 1). As the lift cutting machinesare well known I have illustrated only so much of such machine as isnecessary to enable those familiar with the art to understand and use myinvention.

The recip-rocable plunger 3 above the die carries a cutting block 3aadapted to cooperate with the die in cutting lifts from the sheet ofmaterial fed therebetween. A pair of feed rolls 4, at the infeed side ofthe 'die are adapted to advance the sheet of material to be cut,intermittently between the die and cutting block, after each cuttingoperation of the die. The feed rolls 4 are mounted on shafts 4a whichare intermittently operated to feed the sheet as described, but suchmechanism forms no part of my invention and is not illustrated.

In advance of the feed rolls a table 5 is provided on which the sheet tobe fed is placed by the workman, the inner edge of the sheet beingpositioned against a guide Ed at the rear side of said table.

In my invention I provide the said machine with auxiliary sheet feedingmeans, preferably employing a pair of rolls 6 located at the side of thedie opposite rolls 4. Rolls 6 are adapted to pull the sheet between thedie and block,-see Figs. 1-3. Rolls 6 are mounted on shaft 6a, and maybe driven in unison with and from rolls 4 as described in my divisionalapplication filed November 30, 1936, Serial No. 113,523.

The rolls 6 ensure the sheet passing properly and entirely past the die,and enable a lift to be cut from the heretofore waste stub on the rearend of the strip.

A sheet guide could be attached tothe shaft of the lower feed roll 6,but as such shaft is capable of a limited up and down motion, and thefeed roll mounted on this shaft is held in contact with the board by thepressure spring, I prefer to support the guide on the upper shaft.

The sheet guide and the back gauge 5a form two points of contact whichinsures under normal conditions a true straight progression through themachine of the sheet being cut, more particularly because my improveddie leaves a straight true uninjured edge on the sheet, which edge nextcomes in contact with the guides.

To further explain the feed, the feed rolls 4 push the sheet to die forthe first cut; the set of rolls 6 engage the sheet as it progresses pastthe die and pull the sheet entirely past the die; and both sets of rollsare utilized in order to accomplish the cutting-up of the entire strip,including a last-cut in the last end of the strip which has heretoforealways been waste.

The procedure followed in cutting up a sheet of board on a machineequipped with my improved die and feeding arrangements is as follows:

First the straight hard satisfactory edge of an uncut sheet is placedagainst the back gauge and moved forward over the cutting die andengaged by the feed rolls. The downward thrust of the cutting block cutsout of the sheet a lift (see Fig. 5) and at the proper time during theup-stroke of the plunger and cutting block the feed. rolls 6 pull overthe die a new uncut portion of the board. The reciprocating motion ofthe cutting block and intermittent motion of the feed rolls, properlytimed in relation to each other, causes the sheet to pass between thecutting block and the cutting die for its entire length, and results ina series of lifts being cut-out and leaves a strip of scrap as shown inFig. 6. Fig. '7 shows a strip of scrap as out by the heretofore knownmachines.

Comparing the scrap shown in Fig. '7 with the scrap shown in Fig. 6 itwill be observed that there is no margin left on the side of the scrapFig. 6 like that shown at S in Fig. 7. The size of the pieces of scrapare further reduced by my die, as the straight side or breast of the dieis extended by the projection la, so that automatically each sectionleft by a lift being cut out is cut in two and the resultant scrap is ineffect chopped-up and partly prepared for the fibre beating machines towhich it is generally consigned.

By my invention I have eliminated one waste margin which is inevitablewith the arrangement and machines now in use, and furthermore becausethe edge of the remaining portion of the sheet is left straight true andfirm and not broken, I am able to so adjust the gauges in relation tothe edge of the die that only a very narrow margin is required for thecutting die to enter, as compared to What is now required with presentarrangements.

In machines now in use, as before described, the feed rolls in effectpush the stock to the die. These feed rolls 4 engage the main uncutportion of the board and inasmuch as in the machine, as at presentarranged, the strip being cut is sheared or broken before coming to thedie, there remains on each end of scrap an uncut piece S, of board largeenough to form a lift (see Fig. 7) as no means is provided for carryingthe same to and over the die. My die and machine arrangement pulls in,and cuts a lift from this piece S (see Fig. 6).

I have applied the extended projecting cutting edge Ia to double dies,such for example as shown in Fig. '8. By my invention I produce a betterquality of product in that the sheet is out only with a sharp cuttingedge and not broken anywhere, each lift cut from the board being firmand all edges of lift and sheet remain hard and true.

By my invention I get out of a given siZe sheet more lifts thanheretofore, and further, the scrap resulting from the use of my die andmachine is in smaller pieces and therefore more of it can be loaded byweight in a given size of container, and this facilitates the handlingand transportation or disposition of such scrap.

I am aware that extension edges and protruding cutters have been used.Such construction is known to the cutting-die industry as chisels and isinvariably used to reduce the size of scrap, or to facilitate theremoval of the out parts from the surrounding material; but never to myknowledge has any die been provided with a projection for the expresspurpose of preparing the portion of material being cut for a subsequentrepeated operation. My construction does this, leaving the edge of theuncut portion of material in perfect condition to insert in the machine,and to repeat such operations until the entire sheet has been cut up.

Cir

There are only two methods of mechanically cutting heel lifts. In onesystem of cutting lifts the sheet of material is stripped or cut tonarrow widths in a separate operation, previous to feeding through thecutting machine. In the other system the stripping operation isaccomplished by discs or shears, and this operation takes place justbefore the cutting operation. In either system, a margin is requiredwhich becomes scrap. In my invention there is no stripping or separationof the board in any way; the portion of the sheet being cut is at alltimes a part of the original. This is of distinct advantage when cuttingtwo or more superposed sheets which have been fastened together.

In the cutting of any given size of blank, using a sharp edged cuttingdie of the usual construction, it is absolutely necessary to have apiece of the material being cut of larger dimension than the die-aconsiderable amount of the stock must surround the entire outline of thecutting edge. This is required in order to give the cuttingedge anentrance or bite into the stock. If an attempt is made to cut a blankand not have marginal stock surrounding the outline of the die, the diewill be driven through the stock in a slantwise manner, moving downward,and at the same time, sideways toward the edge which is not entered orengaged in the stock. The result is to cut a blank whose edges will notbe at right angles to the surface, and such blank is generally distortedand not of the same shape as the die. This is due to natural laws andcannot in any way be overcome. My construction complies with thisrequirement, but with this difference as compared to the usualprocedure. That portion of the sheet which is engaged by the projectionon the die serves its purpose in guiding the die and then becomes theguiding edge for the subsequent cut and is not discarded as is done atpresent.

I do not herein claim the machine, as that forms the subject-matter of adivisional application filed November 30, 1936, Serial No. 113,523.

I claim:

1. A blank cutting die having a projection at one side in line with aside and adapted to cut a slit in the sheet in advance of the opening inthe sheet cut by the die, said slit extending sufficiently to registerwith the side of the opening cut in the sheet at the next successiveoperation of the die thereon, whereby a straight clean cut edge isformed on the sheet.

2. A blank cutting die having a substantially straight side and having aprojection at one side in line with such side and adapted to cut a slitin the sheet in advance of the opening in the sheet cut by the die, saidslit extending sufiicient- 1y to register with the side of the openingcut in the sheet at the next successive operation of the die thereon,whereby a straight clean cut edge is formed on the sheet, the extremeend of said projection being slightly incurved.

3. A blank cutting die having a substantially straight side and having aprojection at one side in line with such side and adapted to cut a slitin the sheet in advanace of the opening in the sheet cut by the die,said projection and adjacent straight side of the die producing astraight true edge on the sheet adjacent the line of perforations madeby the die.

4. A blank cutting die having a substantially straight side and having aprojection at one side in line with such side and adapted to cut a slitin the sheet in advance of the opening in the sheet cut by the die, saidslit extending sufficiently to register with the side of the opening cutin the sheet at the next successive operation of the die thereon,whereby a straight true edge is left on the sheet adjacent the line ofperforations made by the die, and the perforated strip is severed fromthe sheet without marginal waste between the adjacent edges of the cutstrip and the sheet.

5. The method of cutting blanks from sheets; consisting in cutting ablank from the sheet and simultaneously cutting a slit in the sheet inadvance of the opening left by the removed blank, said slit extendingsuificiently to register with the side of the next opening cut in thesheet at the next successive cutting operation, said slit forming withthe adjacent straight edges of successive cuts a straight true edge onthe sheet adjacent the line of openings made by the cuts; whereby theperforated cut strip is removed from the sheet without marginal wastebetween the adjacent edges of the cut strip and the remainder of thesheet from which the strip is cut.

LEO F. EXLEY.

